1. Field of Invention
This invention relates generally to processing primal and sub-primal cuts of meat and, more particularly, to removing bones from primal and sub-primal cuts of meat.
2. Background Art
During the disassembly and processing of an animal carcass such as a beef carcass in preparation for delivery of meat products to market, the head is typically removed and the carcass is cut in half lengthwise along the spinal canal. Disassembly of the animal carcass may differ dependent on the type of animal and the protein product being processed. However, in the case of the beef carcass, after cutting the carcass in half, the carcass is then typically divided into its primal meat cut portions such as the “chuck primal cut”. The chuck primal cut of meat is from the head end of the halved carcass and includes the neck, arm bone and shoulder and a portion of the fifth through first rib. A sub-primal cut is a large section of the primal cut. For example, the chuck blade sub-primal cut is a portion of the chuck primal cut. The chuck blade sub-primal cut meat portion includes the neck and shoulder portion and a few inches of the rib.
The removal of bones from primary and sub-primal cuts of meat is very difficult and manually intensive operation. Many primal and sub-primal cuts of meat have a large number of bones of various sizes, shapes and contours that form a complex skeletal structure of the meat cut. For example, the chuck blade has the rib bone skeletal structure and the neck bone skeletal structure. Removing of bones from a sub-primal meat cut is very difficult because of the complex skeletal structure. Also primal and sub-primal cuts of meat particularly from a beef carcass can weigh more than 75 pounds and can have varying sizes, shapes and contours that make it difficult to manually manipulate the meat portion.
A large portion of the disassembly of the meat and removal of bones is performed by utilizing powered cutting tools or hand held knives. Also, some portions of a given primal or sub-primal cut of meat may have bones that have contours that vary considerably with respect to each other which requires the use of a hand held knife that has a flexible blade. Each type of animal carcass and the portion of the carcass being processed, whether it is beef, pork, poultry, mutton, fowl, or similar animal, pose its own unique challenge with regard to bone removal.
For example, the chuck blade is a sub-primal cut of meat and bone that is taken from the front of the beef carcass and presents a difficult and manually intensive operation for removing the bones because of the different types of bone structure and the varying contours of each bone. The chuck blade sub-primal cut can weigh up to 90 pounds and is approximately 24 inches by 18 inches by 8 inches. The final products produced from the chuck blade vary greatly but are predominantly boneless. Typically, the meat of the chuck blade needs to be separated from the bones in one piece with minimal damage to the meat, especially the muscles that are to become the chuck roll. Requiring the meat to be separated from the bone structure in one piece also requires a cutting tool and process that is adapted to follow the varying contours of the bone structure without destroying the meat.
During typical processing of a chuck blade, the person removing the bones must remove the back strap tendon (Ligamenum nuchae), the atlas bone and the rope meat (longus colli). The mock tender (supraspinatus) can be left attached or can be detached from the rest of the muscles depending on the product being made. The process of manually removing the bones from the chuck blade involves manually manipulating the sub primal cut into several orientations so that the bones of the meat portion can be readily accessed. The size and weight and shape of the sub-primal cuts make this manual process very difficult. The bones are typically removed from the chuck blade utilizing a very flexible hand held knife. The individual performing the bone removal process (simply referred to as “de-boning”) manipulates the knife in and around the many various contours of each vertebra.
The large number of bones with the various contours makes this process both difficult and time consuming. The neck vertebrae can be the most difficult in the entire cutting process because each vertebra contains many varying contours. The multiple manipulations of the of the knife performed by the operator in order to follow the various contours of the bone can lead to wrist and arm strains to the arm and wrist utilized to manipulate the knife. In addition, the featherbones channel, and knuckles of the rib bone and thoracic vertebrae skeletal structure all present their own challenges because of their varying shapes, sizes and contours. Navigating a knife in and around these various bone groups results in a wide range of motion and manipulation of the knife and requires a wide range of force to be applied to the knife to navigate through each of these areas which again makes fatigue and injuries to the wrist and arm vary common.
Staffing the chuck blade de-boning position is also challenging because it is difficult to find an individual who is willing and able to withstand the strain imposed on the wrist and arm. The complexity of the bones and the amount of effort required to remove the bones makes the chuck blade de-boning position (chuck de-boning) one of the most difficult staffing challenges in a packing house. The training period is longer than the training period for any other position. Also, many of the people who start the training process for the position move to another position before becoming qualified as a chuck de-boner because of the high level of difficulty. It is the difficulty of the chuck blade de-boning process that is the motivation behind the present invention, however, the present invention can be utilized on various carcass types and portions. Removing bones from beef primals, specifically the chuck, is labor intensive and is the regulating task for the operations of the processing floor. The task is demanding and training along with retention of skill labor has challenged the beef industry for decades.
Several other processes and equipment have been developed or tested over the last decade. One invention is compliant boning, a method in which tension in placed on the bone and opposite tension on the meat. As the opposing forces pull, a manual operation of using a knife cutting the meat from the bone completes the task. This method is quite slow, dangerous, produces poor yields and is logistically impossible to implement in a modern processing facility.
The second effort attempted was to utilize reciprocating chisels to remove the meat from the bones and the concept was tested, producing some results that had limitations. The structure of the reciprocating chisels would not allow the meat to be separated from the bone and left a significant amount of yield, compared to standard hand boning methods. There is a semi automated saw that has two blades at an angle to each other to cut a section of the bone out of the primal.